Carbureting means



May 27, 1958 c. L. AKERS.

cmunmms was Filed Feb. 28. 1955 iii INVENTOR C ILA 7C e rs ATTORNEY.

United States Patent F CARBURETING MEANS Cecil Lynn Akers, Anderson,Ind. Application February 28, 1955, Serial No.-490,861

2 Claims. 01. 12s 117 This invention is designed to provide a new andimproved carbureting means for improving the efliciency of internalcombustion engines and decreasing fuel consumption.

A further object is to obtain the desired results by an improvedapplication of the Venturi tube principle.

Another object is to provide a novel construction which will produce abetter mixture of fuel and air with out the use of delicate andelaborate mechanisms.

With the above and other objects in view that will become apparent asthe nature of the invention is better understood, the same consists inthe novel form, combination and arrangement of parts hereinafter morefully described, shown in the accompanying drawing, and particularlyclaimed.

In the accompanying drawing, the figure is a vertical sectional viewpartly broken away and partly in elevation, showing the invention.

The construction shown in the drawing will be rather specificallydescribed but it is to be understood that variations may be made withoutdeparting from the spirit and scope of the invention as claimed.

A vertically elongated carbureter body 1 is provided, said body havingan air horn 2 at its upper end forconnection with an air cleaner, andhaving a mounting flange 3 at its lower end. The flange 3 is shownsecured by cap screws 4 upon a heat insulator 5 which lies upon acarbureter-mounting boss 6 of an intake manifold 7.

A straight air admitting and mixture conducting passage 8 extends fromthe upper to the lower end of the body 1 and communicates at its lowerend with a passage 9 in the boss 6 of the mainfold. In the upper oranterior portion of the passage 8, a conventional choke valve 10 ismounted; in the lower or posterior end portion of this passage asuitable throttle valve 11 is provided; and between the two valves 10and 11, an auxiliary Venturi 12 and depending skirt 12a are mounted onspider arms or the like 13. The main discharge jet 14 from the fuel bowl15 extends into the auxiliary Venturi 12. Fuel for idling is admittedthrough conventional ports 16 and 17, one of which is controlled asusual by a needle valve 18.

The small opening 19 to the left of the throttle valve 11, is aso-called vacuum spark hole, and the tube 20 is the conventional tube toextend to customary vacuumand spring-actuated spark advancing andretarding means of a conventional ignition distributer.

From the upper end of the horn 2 to a plane 21 near the lower end of theauxiliary Venturi 12, the passage 8 is cylindrical. From the plane 21 toa plane 22 at or near the lower end of the skirt 12 the passage 8 isconically contracted as seen at 23. From the plane 22, the passage 8 isdownwardly flared conically at 24, to a plane near the upper region ofthrottle valve movement. The flare 24 is preferably at approximately 6.

From the plane 25 to a plane 26 near the lower region of throttle valvemovement, the passage 8 is again cylindrical as seen at 27; and fromsaid plane 26 to the lower extremity 28 of the body 1, said passage isagain downice wardly flared conically as at 29. The passage 9 in theboss 6 is also downwardly flared at the same angle as the flare 29 andconstitutes an uninterrupted continuation of the passage 8.

The passages 89 form what may be termed a main Venturi tube having itsthroat at the plane 22. The distance from this throat to the lowerextremity 9 of the passage 9, is approximately four and one-half to sixand one-half times the diameter of the Venturi throat (plane 22).

The following results are obtained:

The flow through the main Venturi neck (at plane 22) is more and thestatic pressure in the throttle chamber 27 is less than in theconventional construction where the throttle is not set in the zone ofthe downstream flare of the Venturi, but is set normally beyond it.

This lower static pressure in the cylindrical throttle chamber 27 willtend to break up the particles of fuel more completely. This breaking upof the fuel particles will permit more oxygen to be made available foruniting with more particles of fuel.

This complete communication of the fuel and oxygen will produce a moreeflicient air-fuel mixture.

This more efficient air-fuel mixture will also favor a more completevaporization of the fuel.

This vaporization will lower the air-fuel mixture temperature. Thusinducing a further drop in pressure even in the throttle chamber, andthis increased vaporization with cooling of the air-fuel mixture willcause the equivalent of a supercharging effect at full throttle.

At full throttle the horsepower of an engine will be increased.

At full throttle the torque of an engine will be increased.

At full throttle the acceleration of an engine will be increased.

At full throttle, due to the supercharging efiect, the intake mainfoldvacuum will lessen to approaching atmosphere pressure; which will reducethe horsepower required during pumping cycle.

At full throttle with better air-fuel mixture and fuel vaporizationbetter fuel distribution will be had.

At full throttle more fuel economy will result in terms of less poundsof fuel per horsepower hour.

At full throttle the overall temperature will be lower due to lessresidual heat caused by less unburned fuel in the exhaust system.

At full throttle longer spark plug life will result, due to lessignition voltage required to break down the spark gap with better fueldistribution and fuel-air mixture, which has a less deterioratingeffect.

At full throttle and higher altitude an engine will perform better andcooler, due to the situation that as a carbureter ascends in altitudethe atmosphere is found to decrease in pressure, temperature, anddensity. The weight of each air (oxygen) charge taken into the enginedecreases with the decrease in air density, cutting down the power inabout the same percentage. In addition, the mixture proportion deliveredby the carbureter is affected, the mixture becoming richer, at a rateinversely proportional to the square root of change in air density.There is less fuel present to start with and therefore will not becomeso over-rich in terms of air density.

At part throttle with the complete communication of fuel and oxygenproducing a more eflicient air-fuel mixture, less fuel will be neededand therefore the throttle can be closed more to accomplish the samework, thus increasing the manifold vacuum which is beneficial to theair-fuel mixture and overall distribution.

At part throttle the economy will be better in terms of miles per gallonof fuel.

At part throttle the increased manifold vacuum will produce moremotivepower to actuate theignition disnibutor over the fullrange of operationwhere needed.

The acceleration of an engine will be better. It is true that a moreeflicient air-fuel mixture is delivered to the combustion chamber,resulting inmore power being produced with less fuel. Therefore, thecontrol throttle .of

the carbureter can beclosed to'a greater degree. Whenever the throttleis closed further, it elevates the suction manifold vacuum measured byinches of mercury. The voverall temperature will be, lower due to lessresidual heat caused by less unburned fuel in the exhaust system. Also,longer sparkplug life will result, due to less ignition voltage requiredto break down the spark gap with better fuel-air mixture, which has lessdeteriorating effect.

a ,At part throttle and higher altitude the engine-will perform betterand cooler due to the situation that as. .a carbureter ascends inaltitude the atmosphere is found to decrease in pressure, temperatureand density. :The

'weight of each air (oxygen) charge taken into the engine decreases withthe decrease in air density, cutting down the power in about the samepercentage. In addition,

the mixture proportion delivered by the earbureter is affected, themixturebecoming richer, at a rate inversely proportional to the squareroot of change in air density. There is-less fuel present to start withand therefore'will notbecome so over-rich in terms of air density.

At cold or hot cranking and idling thelengine will start and run betterdue to higher manifold'.vacuum,

better fuel-air mixture andless fuel required to do the work. Also madepossible is the conservation of crude 4 petroleum by promoting moreefficient utilization of .fuel in an engine.

From the foregoing, it will be se'en'that a novel and advantageousconstruction has been provided. However, attention is again invited tothe possibility of making variations within the scope of the inventionas claimed.

I claim:

1. In a down-draft carbureter for "supplying'a horizontal intakemanifold with anefiicient fuel-air mixture, a substantially verticalconduit having a choke valve at its upper end, a Venturi below it,followed by a cylindrical throttle chamber, and a flaring passageextending/T V downwardly therefrom to said horizontal manifold the angleof flare being substantially the same as that of a the downstreamportion of .said Venturi. a i

2. A combination as defined in claim 1, the major portion of saidflaring passage being formed-in a boss on top of said intake manifold,to which the rest of said carburetor is attached. 7 a

References Cited in-the file of this; patent UNITED STATES PATENTS V V;Balfe Mar. 9,; 1 937 'Bryant [Oct. 19, 1937 Moseley Sept. 9, 1941.Phillips Oct; 20,1953

OTHER REFERENCES r Berrys Handbook of Chemical Engineering, 1st edition,19-34, McGraw-Hill, New York, page 696.

